71 research outputs found
First results of material charging in the space environment
A satellite experiment, designed to measure potential charging of typical thermal control materials at near geosynchronous altitude, was flown as part of the SCATHA program. Direct observations of charging of typical satellite materials in a natural charging event ( 5 keV) are presented. The results show some features which differ significantly from previous laboratory simulations of the environment
MeV magnetosheath ions energized at the bow shock
A causal relationship between midlatitude magnetosheath energetic ions and bow shock magnetic geometry was previously established for ion energy up to 200 keV e−1 for the May 4, 1998, storm event. This study demonstrates that magnetosheath ions with energies above 200 keV up to 1 MeV simply extend the ion spectrum to form a power law tail. Results of cross-correlation analysis suggest that these ions also come directly from the quasi-parallel bow shock, not the magnetosphere. This is confirmed by a comparison of energetic ion fluxes simultaneously measured in the magnetosheath and at the quasi-parallel bow shock when both regions are likely connected by the magnetic field lines. We suggest that ions are accelerated at the quasi-parallel bow shock to energies as high as 1 MeV and subsequently transported into the magnetosheath during this event
THE GENUS HYPOGLOSSUM KÜTZING (DELESSERIACEAE, RHODOPHYTA) IN THE TROPICAL WESTERN ATLANTIC, INCLUDING H. ANOMALUM SP. NOV. 1
Observations are made on the occurrence and distribution of the red algal genus Hypoglossum KÜtzing (Delesseriaceae, Ceramiales) in the tropical western Atlantic. In addition to the type of the genus, H. hypoglossoides (Stackh.) Coll. & Herv., three other species are reported: H. anomalum sp. nov., H. involvens (Harv.) J. Ag., and H. tenuifolium (Harv.) J. Ag. A key is presented to distinguish these four species. The newly described species, H. anomalum, is like other species in the genus in that its branches arise endogenously from the primary axial row but it is unique in that the branches emerge from the parent blade at some point between the midline and the margin of the blade. The new species is reported from Puerto Rico and Florida.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65648/1/j.1529-8817.1986.tb04162.x.pd
Recommendations for Nanomedicine Human Subjects Research Oversight: An Evolutionary Approach for an Emerging Field
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96363/1/j.1748-720X.2012.00703.x.pd
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Robust image analysis with sparse representation on quantized visual features
10.1109/TIP.2012.2219543IEEE Transactions on Image Processing223860-871IIPR
Climate change impacts on groundwater recharge- uncertainty, shortcomings, and the way forward?
An integrated approach to assessing the regional impacts of climate and socio-
economic change on groundwater recharge is described from East Anglia, UK. Many
factors affect future groundwater recharge including changed precipitation and
temperature regimes, coastal flooding, urbanization, woodland establishment, and
changes in cropping and rotations. Important sources of uncertainty and
shortcomings in recharge estimation are discussed in the light of the results.
The uncertainty in, and importance of, socio-economic scenarios in exploring the
consequences of unknown future changes are highlighted. Changes to soil
properties are occurring over a range of time scales, such that the soils of the
future may not have the same infiltration properties as existing soils. The
potential implications involved in assuming unchanging soil properties are
described. To focus on the direct impacts of climate change is to neglect the
potentially important role of policy, societal values and economic processes in
shaping the landscape above aquifers. If the likely consequences of future
changes of groundwater recharge, resulting from both climate and socio-economic
change, are to be assessed, hydrogeologists must increasingly work with
researchers from other disciplines, such as socio-economists, agricultural
modellers and soil scientists
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